Q – When does a device cease being the same device? If a faulty PC motherboard is replaced but the HDD remains unchanged will Windows 10 continue working? We frequently re-install existing Windows operating systems to return to a clean test environment. How many times will we be able to do this with a Windows 10 licence before the re-installs are blocked?

A – Typically, the motherboard is the critical mass here. You can change the hard drive(s) and reinstall, change the video card, even upgrade the processor and Windows will still work on the device. With the free upgrade offer, you must upgrade on a pc that has Windows 7, 8 or 8.1 already installed (except Enterprise and RT editions). Once you have upgraded to Windows 10 on the PC and successfully activated it, you won’t have a Windows 10 product key but you will be able to perform a clean installation and select the Skip button on the product key page. Your PC will activate online automatically so long as the same edition of Windows 10 was successfully activated on the PC by using the free Windows 10 upgrade offer.

You are also allowed to install Windows virtually on the device (but not off the device, e.g. on a network share as that becomes virtual desktop access and requires its own licensing). Section 2d (iv) of the EULA (end user licence agreement):

(iv) Use in a virtualized environment. This license allows you to install only one instance of the software for use on one device, whether that device is physical or virtual. If you want to use the software on more than one virtual device, you must obtain a separate license for each instance.

There are limits on how many times you can activate Windows over the Internet on the same device but if you ever hit that limit, you should be able to perform telephone activation instead. There’s no activation limit enforced in the licence terms. If you move a HDD containing a physical installation of Windows 10 or move a .VHD with Windows installed to another pc, it may work but you may also find that reactivation is triggered by the changes and unless the Windows licence is transferable you’ll be non-compliant.

Q – How will licensing work for people who build their own PC and would normally buy a retail version of Windows? Is that licence going to be transferable to a subsequent build, or is the retail licence going to be limited to that particular PC [and if so, what’s the definition of “that particular PC”]?

A – You can still purchase the retail (FPP) licence of Windows 10, install that on a bare-metal pc and the licence will be transferable to another device (subject to only installing Windows on one device at a time). Preinstalled Windows (OEM) remains non-transferable. Now this does open up new territory for retail Windows; you can buy the retail version once, enjoy updates to Windows and when you want to upgrade your pc, simply transfer your Windows licence to your new pc without requiring an OEM licence. It’s pretty tricky to buy a bare-metal pc from the major manufacturers however and OEM licences became a lot cheaper recently so that may not save much money. Section 4b of the EULA details transfer rights:

b. Stand-alone software. If you acquired the software as stand-alone software (and also if you upgraded from software you acquired as stand-alone software), you may transfer the software to another device that belongs to you. You may also transfer the software to a device owned by someone else if (i) you are the first licensed user of the software and (ii) the new user agrees to the terms of this agreement. You may use the backup copy we allow you to make or the media that the software came on to transfer the software. Every time you transfer the software to a new device, you must remove the software from the prior device. You may not transfer the software to share licenses between devices.

If you are an OEM or System Builder, there remains the COEM (Commercial Original Equipment Manufacturer) product for just that purpose. Windows 8.1 COEM licence removed the DIY (personal use rights) addendum so if you’re building your own pc for personal use, buying the retail product is the correct way to licence.

Q – How is the lifespan of a PC going to be determined? If I have a PC with Windows now, will it still be supported as long as the hardware is still operational, or is there going to be a time limit? Or just a drift towards bits of hardware no longer being supported which would result in being forced to upgrade to a newer PC [and a new Windows licence]? Not everyone cares about the latest capabilities – plenty of people only use PCs to browse the web.

A – No time limit but you’ll find that certain components will become superseded and as such the minimum system requirements for Windows may change. The Microsoft Product Lifecycle pages state:

• Updates are cumulative, with each update built upon all of the updates that preceded it. A device needs to install the latest update to remain supported.• Updates may include new features, fixes (security and/or non-security), or a combination of both. Not all features in an update will work on all devices.• A device may not be able to receive updates if the device hardware is incompatible, lacking current drivers, or otherwise outside of the Original Equipment Manufacturer’s (“OEM”) support period.• Update availability may vary, for example by country, region, network connectivity, mobile operator (e.g., for cellular-capable devices), or hardware capabilities (including, e.g., free disk space).

Q – How much will an OEM version of Win10 cost; a version to be incorporated into our instruments? I cannot find any info on this.

A – There are new editions of Windows 10 called Windows 10 Mobile and Windows 10 Core. These are ideal for industry and embedded devices such as instruments. They’re on the price list and you should be able to get this information from your Microsoft retailer.